/*
** Nofrendo (c) 1998-2000 Matthew Conte (matt@conte.com)
**
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of version 2 of the GNU Library General
** Public License as published by the Free Software Foundation.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
** Library General Public License for more details.  To obtain a
** copy of the GNU Library General Public License, write to the Free
** Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
**
** Any permitted reproduction of these routines, in whole or in part,
** must bear this legend.
**
**
** map046.c
**
** Mapper #46 (Pelican Game Station)
** Implementation by Firebug
** Mapper information courtesy of Kevin Horton
** $Id: map046.c,v 1.2 2001/04/27 14:37:11 neil Exp $
**
*/

#include <noftypes.h>
#include <nes_mmc.h>
#include <nes.h>
#include <libsnss.h>
#include <log.h>

static uint8 prg_low_bank;
static uint8 chr_low_bank;
static uint8 prg_high_bank;
static uint8 chr_high_bank;

/*************************************************/
/* Set banks from the combined register values   */
/*************************************************/
static void map46_set_banks(void)
{
    /* Set the PRG and CHR pages */
    mmc_bankrom(32, 0x8000, (prg_high_bank << 1) | (prg_low_bank));
    mmc_bankvrom(8, 0x0000, (chr_high_bank << 3) | (chr_low_bank));

    /* Done */
    return;
}

/*********************************************************/
/* Mapper #46: Pelican Game Station (aka Rumble Station) */
/*********************************************************/
static void map46_init(void)
{
    /* High bank switch register is set to zero on reset */
    prg_high_bank = 0x00;
    chr_high_bank = 0x00;
    map46_set_banks();

    /* Done */
    return;
}

/******************************************/
/* Mapper #46 write handler ($6000-$FFFF) */
/******************************************/
static void map46_write(uint32 address, uint8 value)
{
    /* $8000-$FFFF: D6-D4 = lower three bits of CHR bank */
    /*              D0    = low bit of PRG bank          */
    /* $6000-$7FFF: D7-D4 = high four bits of CHR bank   */
    /*              D3-D0 = high four bits of PRG bank   */
    if (address & 0x8000)
    {
        prg_low_bank = value & 0x01;
        chr_low_bank = (value >> 4) & 0x07;
        map46_set_banks();
    }
    else
    {
        prg_high_bank = value & 0x0F;
        chr_high_bank = (value >> 4) & 0x0F;
        map46_set_banks();
    }

    /* Done */
    return;
}

/****************************************************/
/* Shove extra mapper information into a SNSS block */
/****************************************************/
static void map46_setstate(SnssMapperBlock* state)
{
    /* TODO: Store SNSS information */
    UNUSED(state);

    /* Done */
    return;
}

/*****************************************************/
/* Pull extra mapper information out of a SNSS block */
/*****************************************************/
static void map46_getstate(SnssMapperBlock* state)
{
    /* TODO: Retrieve SNSS information */
    UNUSED(state);

    /* Done */
    return;
}

static map_memwrite map46_memwrite[] = {{0x6000, 0xFFFF, map46_write}, {-1, -1, NULL}};

mapintf_t map46_intf = {
    46,                     /* Mapper number */
    "Pelican Game Station", /* Mapper name */
    map46_init,             /* Initialization routine */
    NULL,                   /* VBlank callback */
    NULL,                   /* HBlank callback */
    map46_getstate,         /* Get state (SNSS) */
    map46_setstate,         /* Set state (SNSS) */
    NULL,                   /* Memory read structure */
    map46_memwrite,         /* Memory write structure */
    NULL                    /* External sound device */
};

/*
** $Log: map046.c,v $
** Revision 1.2  2001/04/27 14:37:11  neil
** wheeee
**
** Revision 1.1  2001/04/27 12:54:40  neil
** blah
**
** Revision 1.1  2001/04/27 10:57:41  neil
** wheee
**
** Revision 1.1  2000/12/27 19:23:05  firebug
** initial revision
**
**
*/
